| name | translate-copilot-to-claude |
| description | Translate one or more GitHub Copilot native files (AGENTS.md, .agents/skills/*.instructions.md, .codex/agents/*.agent.md, .agents/skills/*.prompt.md, .agents/skills/<name>/SKILL.md) into the native Claude runtime. Classify each section into agent/rule/skill/hook surfaces, diff against existing .claude/ state, produce a translation plan for user approval, and then apply the plan. |
Translate Copilot to Claude
Deterministic translation workflow that ports GitHub Copilot native files into the .claude/ runtime without duplicating content, overwriting user edits, or breaking existing agents.
When to Use This Skill
Use this skill when:
- One or more
.github/ native files must be mirrored into .claude/.
- An agent persona needs to be split across Claude's four runtime surfaces.
- A batch of instructions files must be re-expressed as path-scoped Claude rules.
- A Copilot prompt or skill must be reshaped into a Claude skill.
- The user wants to know what is missing or out-of-date on the Claude side before making changes.
Inputs
Required:
- One or more source paths under
.github/. Accepted types:
AGENTS.md
.agents/skills/<name>.instructions.md
.codex/agents/<name>.agent.md
.agents/skills/<name>.prompt.md
.agents/skills/<name>/SKILL.md
Optional:
mode=plan-only — do not write anything; emit the translation plan and stop.
mode=apply — apply the plan after it is produced and approved in the same turn.
target-scope=<agent|rule|skill|hook|all> — restrict surfaces considered for this run.
timestamp-override=<ISO-8601> — override the auto-generated evidence folder timestamp.
Default mode is plan-only. Apply requires explicit confirmation either via mode=apply or a plain-text approval in the same turn.
Phase 1 — Intake and Section Extraction
For each input file:
- Read the full file with
Read.
- Parse YAML frontmatter (name, description, tools, applyTo, agent, handoffs, model, other keys).
- Split the body into top-level sections delimited by
#, ##, ### headings.
- Classify each section as declarative, procedural, enforceable, identity, or handoff per the taxonomy in Phase 2.
- Record each section as
{source_path, heading, classification, raw_content} in an in-memory list.
Never modify or delete source files. Translation is a copy-forward operation.
Phase 2 — Classification Taxonomy
Apply these decision rules in order. Use the first rule that matches.
2.1 Enforceable (hard gate / hard stop) -> .codex/hooks/
A section is enforceable when it contains:
- phrases such as "hard gate", "hard stop", "must not", "blocked", "forbidden", "zero-regression", "non-negotiable",
- command or path blacklists that should be rejected regardless of model intent,
- per-batch counting or budget limits,
- toolchain-execution verification ("must run", "no unverified work"),
- test-purity forbiddens (tempfile, network, subprocess in tests).
Target:
- A new or updated script under
.codex/hooks/<name>.ps1.
- Registration in
.codex/config.toml under hooks.PreToolUse or hooks.SubagentStop with a matcher that targets the affected tools (Bash, Write|Edit, specific agent names).
Hooks must be read-only validation gates unless the user explicitly authorizes state mutation. Prefer exit code 0 with a {"decision":"block","reason":"..."} JSON response over a non-zero exit when feedback to the agent is required.
2.2 Declarative standards (always-on for matching files) -> .agents/skills/
A section is declarative when it contains:
- coding conventions (naming, typing, imports, error handling),
- test structure requirements,
- toolchain ordering statements,
- file-size limits,
- language-specific style rules.
Target:
-
An existing rule file under .agents/skills/ that already covers the same path scope, merged into place.
-
A new rule file under .agents/skills/<language-or-topic>.md with frontmatter:
---
paths:
- "<glob>"
description: "<one line>"
---
-
If the source frontmatter used applyTo: "<glob>", convert to paths: [<glob>].
2.3 Reusable procedures -> .agents/skills/<name>/SKILL.md
A section is procedural when it contains:
- multi-step workflows ("Phase A", "Phase B", "Workflow", numbered steps),
- reporting templates,
- routing decision tables,
- delegation contracts.
Target:
- An existing skill under
.agents/skills/ when one already covers the same concept (check .agents/skills/<name>/SKILL.md by name and description).
- A new skill at
.agents/skills/<name>/SKILL.md when no coverage exists. Use the make-skill-template skill as the scaffold if needed. Frontmatter must include name and description.
Copilot .agents/skills/*.prompt.md and .agents/skills/<name>/SKILL.md default to this target. Preserve the original name when it does not collide with an existing Claude skill.
2.4 Identity and preload manifest -> .codex/agents/<name>.md
A section belongs on the persona when it contains:
- agent name, description, role summary,
- tool allowlist,
- model selection,
- skill preloads,
- memory scope,
- a short workflow index pointing to preloaded skills,
- stop conditions.
Target:
- An existing agent file under
.codex/agents/<name>.md. Update only the preload list, tools, description, and stop conditions. Keep the body thin.
- A new agent file when the Copilot persona has no Claude counterpart. Do not duplicate rule, skill, or hook content into the persona body.
2.5 Handoffs and delegation -> reference existing skills
Sections describing handoffs to other agents ("delegate to atomic_planner", "handoffs:" frontmatter) should not be duplicated. Reference the canonical skill:
- plan authoring ->
atomic-plan-contract
- remediation ->
remediation-handoff-atomic-planner
- promotion lifecycle ->
feature-promotion-lifecycle
- PR context ->
pr-context-artifacts
- evidence storage ->
evidence-and-timestamp-conventions
2.6 Repo-wide tone / policy precedence -> AGENTS.md
Sections that state cross-cutting repository defaults (tone, policy reading order, architectural overview) belong in AGENTS.md and should be cross-referenced from .agents/skills/ rather than restated.
2.7 Out-of-scope content
The following content is not translated:
- GitHub Actions workflow YAML under
.github/workflows/.
- Codex or other non-Copilot customizations under
.github/codex/ unless explicitly requested.
- Copilot
chatmodes unless the user specifies a target Claude surface.
Phase 3 — Target Resolution
For each classified section, compute a concrete target path:
- Hook:
.codex/hooks/<verb-noun>.ps1 where the verb is check|enforce|validate and the noun is the concern (for example, check-python-test-purity.ps1, enforce-python-batch-budget.ps1).
- Rule:
.agents/skills/<topic>.md where topic is the language (python.md, csharp.md, powershell.md, typescript.md) or cross-cutting concern (tonality.md, general-code-change.md, general-unit-test.md).
- Skill:
.agents/skills/<kebab-case-name>/SKILL.md. Prefer verb-first names for action skills (review-feature, implement-python, invoke-python-engineer) and topic names for contract skills (python-qa-gate, atomic-plan-contract).
- Agent:
.codex/agents/<kebab-case-name>.md. Normalize underscores to hyphens (python_typed_engineer -> python-typed-engineer).
- AGENTS.md: single repo-wide file at the workspace root.
- settings.json:
.codex/config.toml sections hooks and permissions.
Record target paths in the plan. Do not write anything yet.
Phase 4 — Existing State Diff
For every target path:
Read the existing file when it exists.
- Compute a per-section delta:
- add — the section does not exist in the target.
- replace — the section exists but the source content supersedes it (explicit user intent).
- merge — the section exists and source content must be appended or integrated without removing existing text.
- skip — the section is already present verbatim or has a newer canonical form in the target.
- conflict — the source and target disagree on substantive content; requires user decision.
- For
.codex/config.toml, compute add-only updates to hooks.* arrays and permissions.allow. Never remove existing permissions without explicit instruction.
- For agent personas already present, prefer merge over replace to preserve hand-authored guidance.
Flag every conflict row in the plan. Conflicts stop Phase 6 for that row until resolved.
Phase 5 — Translation Plan Artifact
Write a translation plan to artifacts/translation/<timestamp>/plan.md. The timestamp is ISO-8601 UTC, for example 2026-04-18T14-30-00Z, per evidence-and-timestamp-conventions.
Plan structure:
# Translation Plan: <source file basename(s)>
Generated: <timestamp>
Mode: <plan-only | apply>
## Inputs
- <source path 1>
- <source path 2>
## Mapping Table
| Source Section | Classification | Target Path | Action |
|---|---|---|---|
| <source#section-anchor> | rule | .agents/skills/python/SKILL.md#pytest-rules | merge |
| <source#section-anchor> | hook | .codex/hooks/check-python-test-purity.ps1 | add |
| <source#section-anchor> | skill | .agents/skills/python-qa-gate/SKILL.md | add |
| <source#section-anchor> | agent | .codex/agents/python-typed-engineer.toml | merge |
| <source#section-anchor> | settings | .codex/config.toml | add |
## Conflicts (require user decision)
<one row per conflict, or "none">
## New Files
<list of new file paths>
## Updated Files
<list of modified file >
Hooks added:
Permissions added:
Matchers extended:
artifacts/translation//plan.md
artifacts/translation//diff.md (populated after apply)
Always produce the plan artifact, even in mode=apply runs, for auditability.
Phase 6 — Apply (only after explicit approval)
Only execute when one of the following holds:
- The user invoked the skill with
mode=apply.
- The user sent a plain-text approval ("proceed", "apply", "execute the plan") in the same turn after the plan was shown.
Apply order (to minimize breakage):
- Rules — add or merge rule files under
.agents/skills/.
- Skills — add or merge skill files under
.agents/skills/<name>/SKILL.md.
- Hooks — add hook scripts under
.codex/hooks/ and parse-check them with pwsh -NoProfile -Command "[System.Management.Automation.Language.Parser]::ParseFile(..., [ref]$null, [ref]$errors)".
- Agent personas — update
.codex/agents/<name>.md frontmatter (tools, skills, memory) and trim the body to identity + workflow index.
- settings.json — append hook registrations and
Skill(...) permissions. Never rewrite the file; use targeted edits.
- AGENTS.md — append cross-references only; never overwrite existing sections.
- Evidence — write
artifacts/translation/<timestamp>/diff.md summarizing what was actually changed, and store a copy of every new or modified file path under artifacts/translation/<timestamp>/snapshots/.
After apply, run a verification sweep:
- Parse-check every new or changed
.ps1 under .codex/hooks/.
- JSON-parse
.codex/config.toml to confirm validity.
- Confirm every new skill appears in the skills catalog by reading back the first five lines of each target file.
- Report the final mapping table with
done / skipped / conflict-unresolved statuses.
Phase 7 — Reporting
Every completion response must include:
- Inputs — list of source files.
- Mapping summary — counts by classification (rule, skill, hook, agent, settings).
- Action summary — counts by action (add, replace, merge, skip, conflict).
- Files changed — explicit list of created and modified paths.
- Settings delta — hooks and permissions added.
- Evidence paths — artifact locations.
- Conflicts — unresolved conflict rows, or "none".
Guarantees and Prohibitions
- Idempotency: running the skill twice on the same input produces no new changes beyond the regenerated plan artifact.
- No source deletion:
.github/ files are never modified or removed.
- No silent overwrites: existing
.claude/ content is merged by default. Replace requires either user instruction or a conflict row resolved explicitly.
- No hook-based state mutation: hooks generated by this skill are validation-only unless the user authorizes otherwise.
- No settings.json rewrites: only targeted edits that append permissions or matchers.
- No translation of out-of-scope surfaces:
.github/workflows/, .github/codex/, and unrecognized file types are skipped and listed under "Skipped inputs" in the plan.
Classification Quick Reference
| Copilot source pattern | Default Claude target | Notes |
|---|
AGENTS.md | AGENTS.md + AGENTS.md | Tone and precedence only. |
.agents/skills/*.instructions.md (applyTo) | .agents/skills/<topic>.md (paths) | Direct frontmatter rewrite. |
.codex/agents/*.agent.md identity frontmatter | .codex/agents/<name>.md frontmatter | Convert tools: to Claude tool names. |
.codex/agents/*.agent.md "Absolute guardrails / hard gate" | .codex/hooks/*.ps1 + settings.json | Hooks enforce; rules merely document. |
.codex/agents/*.agent.md "Workflow / Phase X" | .agents/skills/<workflow>/SKILL.md | Split per phase when phases are independent. |
.codex/agents/*.agent.md "Design rules / Testing rules" | .agents/skills/<language>.md | Merge under Design Rules / Pytest Rules subheadings. |
.codex/agents/*.agent.md "Handoffs" | Reference existing routing skills | Do not duplicate. |
.codex/agents/*.agent.md "Reporting requirements" | .agents/skills/<name>-qa-gate/SKILL.md or the QA gate skill | Procedure, not identity. |
.agents/skills/*.prompt.md | .agents/skills/<action-name>/SKILL.md | One skill per prompt. |
.agents/skills/<name>/SKILL.md | .agents/skills/<name>/SKILL.md | Near-1:1; reconcile frontmatter schema. |
Invocation Examples
- Translate a single agent persona, plan only:
translate-copilot-to-claude .codex/agents/python-typed-engineer.toml
- Translate a set of instruction files and apply:
translate-copilot-to-claude .agents/skills/python-code-change/SKILL.md .agents/skills/python-unit-test/SKILL.md mode=apply
- Translate an entire agent bundle (persona + its referenced instructions):
translate-copilot-to-claude .codex/agents/csharp-typed-engineer.toml .agents/skills/csharp-code-change/SKILL.md .agents/skills/csharp-unit-test/SKILL.md target-scope=all